Congratulations for completing the 250 Box Challenge! While I will accept your submission, it would have been better to have included the link to your original work. Luckily I dug it up and since all your boxes are there your critique will proceed.

I can see that you put a lot of effort into the challenge and your boxes are coming along well. Your lines are straight and more confident looking. You do a good job of adding your extra line weight with confidence and it blends well with your original marks. Make sure to keep practicing that in your warm ups! You also do a better job of getting your sets of parallel lines to converge more consistently towards their shared vanishing points!

Finally while your convergences do improve overall I think this diagram will help you further develop that skill as you continue through Drawabox. So, when you are looking at your sets of lines you want to be focusing only on the lines that share a vanishing point. This does not include lines that share a corner or a plane, only lines that converge towards the same vanishing point. Now when you think of those lines, including those that have not been drawn, you can think about the angles from which they leave the vanishing point. Usually the middle lines have a small angle between them, and this angle will become negligible by the time they reach the box. This can serve as a useful hint.

Congrats again and good luck with lesson 2!